This was very ambitious! Great work overall. Other people have already commented a lot of similar things I would have said. Its mostly just polish that it needs - gun sounds are a bit weak, I'd source some better ones. The lighting and textures could do with some work.
But those are nit picks and stuff that can be done with more time. What you managed to do in the gamejam's timeframe is super impressive. There's lots to explore and little secrets to find and I can just tell you had fun making it.
Also, the sneaky guard hiding in the booth waiting to push you off the cliff was my favourite bit haha.